The present disclosure relates generally to photodisruption induced by a pulsed laser beam and the location of the photodisruption so as to treat a material, such as a tissue of an eye. Although specific reference is made to cutting tissue for surgery such as eye surgery, embodiments as described herein can be used in many ways with many materials to treat one or more of many materials, such as cutting of optically transparent materials.
Cutting of materials can be done mechanically with chisels, knives, scalpels and other tools such as surgical tools. However, prior methods and apparatus of cutting can be less than desirable and provide less than ideal results in at least some instances. For example, at least some prior methods and apparatus for cutting materials such as tissue may provide a somewhat rougher surface than would be ideal. Pulsed lasers can be used to cut one or more of many materials and have been used for laser surgery to cut tissue.
The prior methods and apparatus to incise tissue with laser beams can be less than ideal in at least some instances. For example, the laser beam may not incise tissue at the target location, and the actual location of the laser beam incision may vary from the targeted position. Although calibration can be used to improve the accuracy of the prior laser surgery systems, calibration can be time consuming and the alignment of the system components may drift over time so as to require additional calibration in at least some instances. Also, the prior methods and apparatus of calibrating laser systems can be less than ideal. For example, after calibration of the laser system, the targeted incision location can vary from the actual location of the incision.
In light of the above, it would be desirable to have improved methods and apparatus of treating materials with laser beams, such as the surgical cutting of tissue to treat cataracts and refractive errors of the eye. At least some of the above deficiencies of the prior methods and apparatus are overcome by the embodiments described herein.